loess deposit is one of the most important quaternary deposits of northeastern parts of iran which have high erosion rate. this study was performed with field- rainfall- simulator which has a plot area of 1 m2 in gorganrood drainage basin to determine the effective factors on sediment yield. landuse, slope and erosion feature maps were overlaid in gis to obtain land unit map. then on work units...

Organic agricultural systems are often assumed to be more sustainable than conventional farming, yet there has been little work comparing surface water quality from organic and conventional production, especially under the same cropping sequence. Our objective was to compare nutrient and sediment losses, as well as sweet corn ( L. var. ) yield, from organic and conventional production with conv...

At present the large scale vegetation restoration and intensive oil exploiting had brought huge influence on local environment in Yan'an region. the sediment yield data form series experiment plots and hydrological monitoring station in the Yan'an watershed after one rainfall event on July 2, 2005, which included sediment from different land uses (crop-land plot, vegetation plots, hard road sur...

Surface runoff and sediment transport in ̄uence soil quality and the quality of receiving waters. Simulation models are useful tools to describe drainage behavior and sediment yield to develop management strategies for agricultural waters. The objective of this study was to investigate the performance of the Agricultural Non-Point Source Pollution Model (AGNPS) and modi®ed versions comparing mea...

Suspended sediment concentration of a river can provide very important perspective on erosion or soil loss of one river basin ecosystem. The changes of land use and land cover, such as deforestation or afforestation, affect sediment yield process of a catchment through changing the hydrological cycle of the area. A sediment rating curve can describe the average relation between discharge and su...

Impaired water quality caused by human activity and the spread of invasive plant and animal species has been identified as a major factor of degradation of coastal ecosystems in the tropics. The main goal of this study was to evaluate the performance of AnnAGNPS (Annualized NonPoint Source Pollution Model), in simulating runoff and soil erosion in a 48 km watershed located on the Island of Kaua...

the adequacy of the swat model in the estimation of runoff, sediment yield and nitrate loss in the gorganrood watershed was tested, using the existing spatial database as the primary data. the model was then executed for a 31-years’ time period. in combination with the swat model, the sequential uncertainty fitting program (swat-cup and sufi-2) was added used to calibrate and validate a hydrolo...

Papers published in Hydrology and Earth System Sciences Discussions are under open-access review for the journal Hydrology and Earth System Sciences Abstract In the present work, an application of statistical regression relationships utilising ge-omorphic parameters is attempted in a spatially distributed mode, in order to predict the amount of river sediment supply at varying sections of the d...